Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 5:59AM||Sunset 8:21PM||Friday August 7, 2020 2:00 PM CDT (19:00 UTC)||Moonrise 9:37PM||Moonset 8:51AM||Illumination 85%|
7 Day Forecast for Marine Location Near Sparta, WIHourly EDIT Help
Area Discussion for - La Crosse, WI  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS63 KARX 071800 AFDARX
Area Forecast Discussion National Weather Service La Crosse WI 100 PM CDT Fri Aug 7 2020
SHORT TERM. (Today and tonight) Issued at 317 AM CDT Fri Aug 7 2020
As of 3 AM, a few showers were starting to pop up near the I-35 corridor as some modest moisture transport was pointing toward the area. Expect these to continue moving northeast into this morning, mainly moving through portions of southeast Minnesota before dissipating near the Mississippi River as moisture transport tapers off. This should give way to a quiet day today (other than some breezy southerly winds) as upper level ridging builds in.
Attention then turns to the shortwave moving through South Dakota this morning. It will continue northeastward into northern Minnesota by this afternoon, with plenty of associated showers and storms. While the wave and those storms will stay well north of the forecast area, we'll have to keep an eye on southward progress of any outflow boundary emanating from them. Moisture transport will ramp up this evening, and while it doesn't look overly strong, it would likely be enough to get showers and storms to go up along any boundary sitting out there. A handful of CAM solutions suggest this occurs, but differ a bit on exactly where those storms would track and how widespread they would be. In general, they would indicate a line moving southeast into the area by the early morning hours Saturday. Storms would have some capping to contend with, but should some storms get going, the warm nose would likely cool enough to allow them to persist into Saturday morning. Wouldn't think they'd be severe given the timing, but perhaps some gusty winds would be possible.
Beyond the potential line of storms in the morning, the rest of Saturday looks to have some smaller shower and storm chances as additional weak shortwave energy slides through. However, a stout cap at the bottom of an elevated mix layer looks like it would limit storm coverage quite a bit.
LONG TERM. (Saturday through Thursday) Issued at 317 AM CDT Fri Aug 7 2020
The main theme of the long term forecast period will be weak shortwaves sliding through the forecast area and providing shower and storm chances. Unfortunately, a wide variety of model solutions still exist regarding timing and strength of the various systems, so forecast confidence remains rather low. For Sunday, the general consensus would suggest only weak forcing and fairly strong capping in place, which would limit storm coverage quite a bit. While there does look to be a few thousand J/kg of MUCAPE, dry air in the mid- levels would make it tough for any elevated storms to get going. That said, the 07.00Z ECMWF and NAM produce interesting (but different) solutions that would favor more of a strong to possibly severe storm threat.
The ECMWF solution would suggest an MCS develops over South Dakota Saturday night and moves into the forecast area Sunday afternoon. It would appear there would be plenty of instability to maintain it as moves eastward, though only modest shear would suggest it may struggle a bit at times.
The NAM, on the other hand, would suggest we stay clear through the morning with storms developing by the afternoon as a shortwave moves through. While this is the general idea with most solutions, NAM soundings indicate the capping present in other solutions erodes by mid-afternoon, leading to SBCAPE values near 4000 J/kg (accounting for likely overdone surface dewpoints).
So while these two solutions look to be outliers compared to the GFS and GEFS ensemble members, they're something to certainly be aware of. More confidence exists in shower and storm chances then Sunday night as surface cold front slides through. Timing would not be favorable for severe weather (moving into western portions of the forecast area after midnight). Beyond that, as previously mentioned, various shortwaves look to slide through zonal flow aloft, bringing additional spotty shower and storm chances through Thursday. However, confidence is low in timing and strength given model differences.
Temperature-wise, a warm, humid weekend is on tap, owing to persistent southerly flow. Sunday appears to be the warmest day, with highs in the 80s to lower 90s and heat index values in the 90s to near 100 (unless we end up with more storm coverage than expected). Looks like we'll remain below Heat Advisory criteria at this time, but still warm nonetheless. We'll see a little relief behind the aforementioned cold front that passes Sunday night, with highs getting back in the 70s and 80s through mid-week.
AVIATION. (For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1256 PM CDT Fri Aug 7 2020
VFR conditions through 06Z with variable clouds fl035-250 . however with moisture influx into the area expect mvfr conditions to expand into KRST/KLSE overnight. RAP/LAMP data hinting at ifr conditions may also develop Meanwhile. a complex of thunderstorms is forecast to develop across Michigan and move into northwest Wisconsin after 04Z. The better forcing for the storms will be will to the north of the TAF sights, however storms could develop southward into the moist and unstable air 09-11Z before weakening. The maximum elevated instability is over the KRST/KLSE areas around 12Z. Additional showers and thunderstorms could remain in the area through 16Z. Confidence is too low to include in the TAFs at this time. Have some time over the next six to nine hours to assess how the convective complex is evolving and how the developing low level jet across Iowa is impacting convection. South winds 12 to 16kts with some gusts to around 25kts this afternoon generally decrease to around 12 kts overnight.
ARX WATCHES/WARNINGS/ADVISORIES. WI . None. MN . None. IA . None.
SHORT TERM . Rieck/CA LONG TERM . CA AVIATION . Zapotocny
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Sparta, Sparta / Fort McCoy Airport, WI||4 mi||65 min||S 10||10.00 mi||Mostly Cloudy||80°F||58°F||48%||1019.3 hPa|
|Black River Falls Area Airport, WI||22 mi||65 min||S 7||10.00 mi||Mostly Cloudy||81°F||58°F||47%||1018.6 hPa|
|La Crosse - La Crosse Regional Airport, WI||24 mi||67 min||S 14||10.00 mi||Mostly Cloudy||84°F||61°F||46%||1017.4 hPa|
Link to 5 minute data for KCMY
Wind History from CMY (wind in knots)
|1 day ago||NW||Calm||W||SW||S||S||Calm||E||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||SE||S||SW||S||S|
|2 days ago||NW||N||NW||NW||N||W||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NW||W |
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GEOS Local Image of EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for La Crosse, WI (15,3,4,5)(on/off)  Help
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